Project Abstract Dr. Layton is an assistant professor of health care policy in the Department of Health Care Policy at Harvard Medical School. He has a PhD in economics from Boston University and was previously a National Institute of Mental Health Postdoctoral Research Fellow at Harvard Medical School. He has expertise in theoretical and empirical microeconomics, with a specific focus on the application of quasi-experimental methods to questions related to health economics. His specific area of research is the economics of health insurance markets, and his previous work has focused on the Medicare Advantage program and the state and federal Health Insurance Marketplaces. Dr. Layton has a specific interest in vulnerable groups like low-income households, children, and the disabled. This interest has led him to Medicaid, a program that has changed dramatically over the last two decades both in size and structure, with the most significant change arguably being the shift to providing Medicaid benefits via private Medicaid Managed Care (MMC) plans. His primary long-term career goal is to become a national expert in MMC. The purpose of this Mentored Research Scientist Research Career Development Award (K01) is to help him fulfill that goal. Relatively low payment levels in Medicaid have led to concerns about the quality of care provided to individuals enrolled in the program. Because of this, any Medicaid expert must also be a quality expert. The training plan in this proposal focuses on helping Dr. Layton achieve his goal of developing the quality and outcomes measurement skills he needs to contribute meaningfully to this area. The plan includes formal and informal coursework with clinical researchers who are experts in quality measurement, and a one-year ?apprenticeship? with experts in this area. Because Medicaid is a program where states have a great deal of flexibility and control leading to wide variation across and substantial complexity within state Medicaid programs, relationships between stakeholders and researchers are critical for producing relevant and accurate scholarship on Medicaid. The second part of the training plan focuses on Dr. Layton's development of relationships with Medicaid stakeholders that will benefit him throughout his career. The research project proposed as part of this award focuses on MMC. In the first part of the project, Dr. Layton will leverage random assignment of Medicaid recipients to Medicaid plans to bring experimental evidence to the question of whether patients receive higher quality care and achieve better health outcomes under public fee-for-service Medicaid or under private MMC plans. In the second part of the project, Dr. Layton will bring quasi-experimental methods to questions about how states should structure their MMC programs. Many states have already decided to go ?all-in? on MMC, making questions related to MMC program structure (i.e. plan payment, plan selection, etc.) some of the most relevant in the Medicaid area. After accomplishing the training and research aims in this project, Dr. Layton will be well on his way to becoming and independent investigator and expert in MMC.